That the NSA is doing this is not newsworthy; Edward Snowden has told the world of this during the past 10 months. What is newsworthy is that the NSA has admitted it, and those admissions have far-reaching consequences.

Since the Snowden revelations first came to light last June, the NSA has steadfastly denied them. Mr. Clapper has denied them. The recently retired head of the NSA, Gen. Keith Alexander, has denied them. Even President Obama has stated repeatedly words to the effect that “no one is reading your emails or listening to your phone calls.”

The official NSA line on this has been that the Foreign Intelligence Surveillance Act (FISA) court has issued general warrants for huge amounts of metadata only, but not content. Metadata consists of identifying markers on emails, text messages and telephone calls. These markers usually identify the computer from which an email or text was sent or received, and the time and date of the transmission, as well as the location of each computer. Telephone metadata is similar. It consists of the telephone numbers used by the callers, the time, date and duration of the call, and the location of each telephone used in the call.

American telecommunications and Internet-service providers have given this information to the NSA pursuant to warrants issued by secret FISA court judges. These warrants are profoundly unconstitutional, as they constitute general warrants.

General warrants are not obtained by presenting probable cause of crime to judges and identifying the person from whom data is to be seized, as the Constitution requires. Rather, general warrants authorize a government agent to obtain whatever he wants from whomever he wants it.

These general warrants came about through a circuitous route of presidential, congressional and judicial infidelity to the Constitution during the past 35 years. The standard that the government must meet to obtain a warrant from a FISA court judge repeatedly has been lessened from the constitutional requirement of probable cause with a short jump for NSA lawyers to persuade FISA court judges to sign general warrants for all communications of everyone in America.

The NSA argued that it was not accessing the content of these communications; it was merely storing metadata and then using algorithms to determine who was talking to whom.

This was all done in secret — so secret that the president would lie about it; so secret that Congress, which supposedly authorized it, was unaware of it; and so secret that the FISA court judges themselves do not have access to their own court records. (Only the NSA does.)

It was to further this public facade that Mr. Clapper lied to the Senate Intelligence Committee last year when he replied to a question from Mr. Wyden about whether the NSA was collecting massive amounts of data on hundreds of millions of Americans by replying, “No” and then adding, “Not wittingly.” The stated caveat in the NSA facade was a claim that if its agents wanted to review the content of any data the NSA was storing, they identified that data and sought a warrant for it.

This second round of warrants is as unconstitutional as the first round because these warrants, too, are based on NSA whims, not probable cause of crime. Yet it is this second round of warrants that Mr. Clapper’s letter revealed did not always exist.

Mr. Snowden, in an act of great personal sacrifice and historic moral courage, directly refuted Mr. Clapper by telling reporters that the NSA possessed not just metadata, but also content — meaning the actual emails, text messages and recordings of telephone calls. He later revealed that the NSA also has the content of the telephone bills, bank statements, utility bills and credit card bills of everyone in America.

One wonders whether Mr. Obama was duped by Mr. Clapper when he denied all this, or whether the president just lied to the American people as he has done in the past.

One also wonders how the Obama administration could do all this with a straight face. This is the same government that unsuccessfully prosecuted former New York Yankees pitcher Roger Clemens twice for lying to a congressional committee about the contents of his urine.

Shouldn’t we expect Mr. Clapper to be prosecuted for lying to a congressional committee about the most massive government plot in U.S. history to violate the Fourth Amendment? Don’t hold your breath: The president will protect his man.

Yet Congress could address this independent of a president who declines to prosecute his fellow liars. Congress could impeach Mr. Clapper, and the president would be powerless to prevent it. If Congress does that, it would be a great step forward for the rule of law and fidelity to the Constitution. If Congress does nothing, we can safely conclude that it is complicit in these constitutional violations.

If members of Congress will not impeach an officer of the government when they themselves are victims of his crimes because they fear the political consequences, do they still believe in the Constitution?

Andrew P. Napolitano, a former judge of the Superior Court of New Jersey, is an analyst for the Fox News Channel. He has written seven books on the U.S. Constitution.